No disrespect intended, but what point are you trying to get across? What dress code would you prefer? Don't forget that a lot of people who travel on the low cost carriers (worldwide) are often first time travellers, who as far as they are concerned dress standards on bus are similar to what you would wear on an aircraft. They dont think in airline terminology and dont possess an aviation mindset - they are thinking "I have 2 1/2 hours with the kids trapped inside a shiny metal tube, what can we all wear that will be most comfortable for us".
Flying is no longer limited to the wealthy few, it has not been for quite some time now, and as long as people are wearing clothes that are adequately protective and non-offensive, then I fail to see any problem (although the one thing I will agree with is I would like to see closed in shoes a standard requirement).
Or perhaps you can turn the coin - what about all those extrememly expensive (read: overpriced) FCUK shirts etc? They are dressy, expensive blah blah, but no doubt considered offensive by a lot of australians (particularly older generations)?
[Edit: I would like to see a standard dress code of at least smart casual attire, but realistically it unfortunately just cannot be expected]